Multiple Sclerosis Disease Onset Research Articles

Not all roads lead to the immune system: the genetic basis of multiple sclerosis severity.

Multiple sclerosis is a leading cause of neurological disability in adults. Heterogeneity in multiple sclerosis clinical presentation has posed a major challenge for identifying genetic variants associated with disease outcomes. To overcome this challenge, we used prospectively ascertained clinical outcomes data from the largest international multiple sclerosis registry, MSBase. We assembled a cohort of deeply phenotyped individuals of European ancestry with relapse-onset multiple sclerosis. We used unbiased genome-wide association study and machine learning approaches to assess the genetic contribution to longitudinally defined multiple sclerosis severity phenotypes in 1813 individuals. Our primary analyses did not identify any genetic variants of moderate to large effect sizes that met genome-wide significance thresholds. The strongest signal was associated with rs7289446 (β = -0.4882, P = 2.73 × 10-7), intronic to SEZ6L on chromosome 22. However, we demonstrate that clinical outcomes in relapse-onset multiple sclerosis are associated with multiple genetic loci of small effect sizes. Using a machine learning approach incorporating over 62 000 variants together with clinical and demographic variables available at multiple sclerosis disease onset, we could predict severity with an area under the receiver operator curve of 0.84 (95% CI 0.79-0.88). Our machine learning algorithm achieved positive predictive value for outcome assignation of 80% and negative predictive value of 88%. This outperformed our machine learning algorithm that contained clinical and demographic variables alone (area under the receiver operator curve 0.54, 95% CI 0.48-0.60). Secondary, sex-stratified analyses identified two genetic loci that met genome-wide significance thresholds. One in females (rs10967273; βfemale = 0.8289, P = 3.52 × 10-8), the other in males (rs698805; βmale = -1.5395, P = 4.35 × 10-8), providing some evidence for sex dimorphism in multiple sclerosis severity. Tissue enrichment and pathway analyses identified an overrepresentation of genes expressed in CNS compartments generally, and specifically in the cerebellum (P = 0.023). These involved mitochondrial function, synaptic plasticity, oligodendroglial biology, cellular senescence, calcium and G-protein receptor signalling pathways. We further identified six variants with strong evidence for regulating clinical outcomes, the strongest signal again intronic to SEZ6L (adjusted hazard ratio 0.72, P = 4.85 × 10-4). Here we report a milestone in our progress towards understanding the clinical heterogeneity of multiple sclerosis outcomes, implicating functionally distinct mechanisms to multiple sclerosis risk. Importantly, we demonstrate that machine learning using common single nucleotide variant clusters, together with clinical variables readily available at diagnosis can improve prognostic capabilities at diagnosis, and with further validation has the potential to translate to meaningful clinical practice change.

Using personalized prognosis in the treatment of relapsing multiple sclerosis: A practical guide.

The clinical course of multiple sclerosis (MS) is highly variable among patients, thus creating important challenges for the neurologist to appropriately treat and monitor patient progress. Despite some patients having apparently similar symptom severity at MS disease onset, their prognoses may differ greatly. To this end, we believe that a proactive disposition on the part of the neurologist to identify prognostic “red flags” early in the disease course can lead to much better long-term outcomes for the patient in terms of reduced disability and improved quality of life. Here, we present a prognosis tool in the form of a checklist of clinical, imaging and biomarker parameters which, based on consensus in the literature and on our own clinical experiences, we have established to be associated with poorer or improved clinical outcomes. The neurologist is encouraged to use this tool to identify the presence or absence of specific variables in individual patients at disease onset and thereby implement sufficiently effective treatment strategies that appropriately address the likely prognosis for each patient.

The Blood-Brain Barrier-A Key Player in Multiple Sclerosis Disease Mechanisms.

Over the past decade, multiple sclerosis (MS), a chronic neuroinflammatory disease with severe personal and social consequences, has undergone a steady increase in incidence and prevalence rates worldwide. Despite ongoing research and the development of several novel therapies, MS pathology remains incompletely understood, and the prospect for a curative treatment continues to be unpromising in the near future. A sustained research effort, however, should contribute to a deeper understanding of underlying disease mechanisms, which will undoubtedly yield improved results in drug development. In recent years, the blood–brain barrier (BBB) has increasingly become the focus of many studies as it appears to be involved in both MS disease onset and progression. More specifically, neurovascular unit damage is believed to be involved in the critical process of CNS immune cell penetration, which subsequently favors the development of a CNS-specific immune response, leading to the classical pathological and clinical hallmarks of MS. The aim of the current narrative review is to merge the relevant evidence on the role of the BBB in MS pathology in a comprehensive and succinct manner. Firstly, the physiological structure and functions of the BBB as a component of the more complex neurovascular unit are presented. Subsequently, the authors review the specific alteration of the BBB encountered in different stages of MS, focusing on both the modifications of BBB cells in neuroinflammation and the CNS penetration of immune cells. Finally, the currently accepted theories on neurodegeneration in MS are summarized.

Role of aging-associated Treg cell accumulation in experimental autoimmune encephalomyelitis (EAE) — a model of late-onset multiple sclerosis (MS)

Abstract MS, a T cell-mediated autoimmune demyelinating disease of the central nervous system (CNS), has not been sufficiently studied in the elderly, despite instances of late-onset MS. Regulatory T (Treg) cells play an ameliorative role in MS disease onset and severity. Given that the aged immune system exhibits relatively enhanced thymic Treg cell generation and accumulated peripheral Treg cells, the role of Treg cell in aged MS patients remains to be elucidated. Using the mouse model EAE, we found that the aged mouse late-onset EAE occurs with two disease types. In Type I, EAE onset was delayed in the age mice, but the disease became more severe once onset. Alternatively, in Type II, some aged mice never developed severe symptoms than young mice until a second antigen challenge was given, which led to more a progressive disease course than their young counterparts. These features were potentially associated with a disparate distribution of Treg cells in the aged peripheral lymphoid tissues and CNS during the disease. The aged EAE mice had a higher proportion of polyclonal Treg cells in the peripheral lymphoid tissues, but a lower proportion of Treg cells specific for myelin oligodendrocyte glycoprotein (MOG) in the CNS, compared to young counterparts. Transient inhibition of accumulated polyclonal Treg cells in the periphery partially ameliorated disease severity in the aged mice, which was accompanied by increased MOG-specific Treg cells in the CNS. Therefore, we suggest that accumulated polyclonal Treg cells in the aged periphery are detrimental for CNS repair processes during neuronal inflammation in aged MS mice, potentially due to hampering trafficking of MOG-specific Treg cells into the CNS.

The Role of Autoimmunity-Related Gene CLEC16A in the B Cell Receptor-Mediated HLA Class II Pathway.

C-type lectin CLEC16A is located next to CIITA, the master transcription factor of HLA class II (HLA-II), at a susceptibility locus for several autoimmune diseases, including multiple sclerosis (MS). We previously found that CLEC16A promotes the biogenesis of HLA-II peptide-loading compartments (MIICs) in myeloid cells. Given the emerging role of B cells as APCs in these diseases, in this study, we addressed whether and how CLEC16A is involved in the BCR-dependent HLA-II pathway. CLEC16A was coexpressed with surface class II-associated invariant chain peptides (CLIP) in human EBV-positive and not EBV-negative B cell lines. Stable knockdown of CLEC16A in EBV-positive Raji B cells resulted in an upregulation of surface HLA-DR and CD74 (invariant chain), whereas CLIP was slightly but significantly reduced. In addition, IgM-mediated Salmonella uptake was decreased, and MIICs were less clustered in CLEC16A-silenced Raji cells, implying that CLEC16A controls both HLA-DR/CD74 and BCR/Ag processing in MIICs. In primary B cells, CLEC16A was only induced under CLIP-stimulating conditions in vitro and was predominantly expressed in CLIPhigh naive populations. Finally, CLIP-loaded HLA-DR molecules were abnormally enriched, and coregulation with CLEC16A was abolished in blood B cells of patients who rapidly develop MS. These findings demonstrate that CLEC16A participates in the BCR-dependent HLA-II pathway in human B cells and that this regulation is impaired during MS disease onset. The abundance of CLIP already on naive B cells of MS patients may point to a chronically induced stage and a new mechanism underlying B cell-mediated autoimmune diseases such as MS.

Alterations of Gut Microbiota and the Brain-Immune-Intestine Axis in Patients With Relapsing-Remitting Multiple Sclerosis After Treatment With Oral Cladribine: Protocol for a Prospective Observational Study.

BackgroundImmunological factors are the key to the pathogenesis of multiple sclerosis (MS). Conjointly, environmental factors are known to affect MS disease onset and progression. Several studies have found that the intestinal microbiota in MS patients differs from that of control subjects. One study found a trend toward lower species richness in patients with active disease versus in patients in remission. The microbiota plays an important role in shaping the immune system. Recent studies suggest the presence of an association between the gut microbiota and inflammatory pathways in the central nervous system. However, the function of this brain-immune-intestine axis and its possible value for predicting treatment effect in MS patients is currently unknown.ObjectiveOur goal is to examine if the changes in gut and oral microbiota and simultaneous changes in the immune response are a predictor for the treatment response in subjects with active relapsing-remitting MS (RRMS) who are being treated with oral cladribine.MethodsThis is a prospective, observational, multicenter study. Eligible subjects are patients with RRMS, between the ages of 18 and 55 years, who will start treatment with oral cladribine. Patients who used probiotics 1 month prior to the start of oral cladribine will be excluded. At baseline (ie, before start) and after 3, 12, and 24 months, the Expanded Disability Status Scale (EDSS) score will be assessed and fecal, oral, and blood samples will be collected. Also, subjects will be asked to register their food intake for 7 consecutive days following the visits. After 24 months, a magnetic resonance imaging (MRI) assessment of the brain will be performed. Responders are defined as subjects without relapses, without progression on the EDSS, and without radiological progression on MRI.ResultsInclusion started in January 2019. A total of 30 patients are included at the moment. The aim is to include 80 patients from 10 participating centers during a period of approximately 24 months. Final results are expected in 2024.ConclusionsThe results of the BIA Study will contribute to precision medicine in patients with RRMS and will contribute to a better understanding of the brain-immune-intestine axis.International Registered Report Identifier (IRRID)DERR1-10.2196/16162

Socioeconomic deprivation increases the risk of disability in multiple sclerosis patients

BackgroundLittle is known about the association between the socioeconomic status (SES) and disability risk of patients with Multiple Sclerosis (MS). ObjectiveThe aim of this study was to assess the influence of low SES, otherwise known as socioeconomic deprivation, on the disability risk of MS patients. Methods4498 patients with a relapsing MS disease onset between 1982 and 2017 were included from the databases of three MS expert centres (Caen, Rouen, Lille) of the French Observatory for MS (OFSEP). Sociodemographic and clinical data of 3641 patients were used for the analysis. The EDI (European Deprivation Index), an ecological and composite indicator was used to assess the level of socioeconomic deprivation. Comparisons of time to reach EDSS 4 and EDSS 6, chosen as disability milestones, according to EDI quintiles were performed by Kaplan-Meier analysis. Cox proportional hazard models were also conducted to assess the risk according to EDI quintiles with adjustment to sex, MS type and age at disease onset. ResultsIn the study population (n = 3641), most patients were women (71.9%; n = 2664). The mean age at disease onset was 32.2 years (SD =9.7). 1684 (46%) patients reached EDSS 4 and 1005 (28%) reached EDSS 6. The risk of reaching EDSS 4 and EDSS 6 in more socioeconomically deprived patients (EDI Q5) was independently higher than in the less socioeconomically deprived patients (EDI Q1) (HR=1.37 95%CI [1.15–1.64]) to reach EDSS 4 and (HR=1.42 95%CI [1.13–1.75]) to reach EDSS 6. ConclusionsIn this study, socioeconomic deprivation was significantly associated to the disability risk in MS patients. Better knowledge of socioeconomic disparities in MS may help adapt care to settings and improve the quality of care given to patients in the future.

Aging and Brain Atrophy in Multiple Sclerosis.

Brain atrophy accelerates at the age of 60 in healthy individuals (HI) and at disease onset in multiple sclerosis (MS) patients. Whether there is an exacerbating effect of aging superimposed on MS-related brain atrophy is unknown. We estimated the aging effect on lateral ventricular volume (LVV) and whole brain volume (WBV) changes in MS patients. 1,982 MS patients (mean follow-up: 4.8 years) and 351 HI (mean follow-up: of 3.1 years), aged from 20 to 79 years old (yo), were collected retrospectively. Percent LVV change (PLVVC) and percent brain volume change (PBVC) on 1.5T and 3T MRI scanners (median of 3.9 scans per subject) were calculated. These were determined between all-time points and subjects were divided in six-decade age groups. MRI differences between age groups were calculated using analysis of covariance (ANCOVA). Compared to HI, at first MRI, MS patients had significantly increased LVV in the age groups: 30-39 yo, 40-49 yo, 50-59 yo, 60-69 yo (all P < .0001), and 70-79 yo (P = .029), and decreased WBV in the age groups: 20-29 yo (P = .024), 30-39 yo (P = .031), 40-49 yo, and 50-59 yo (all P < .0001). Annualized PLVVC was significantly different between the age groups 20-59 and 60-79 yo in MS patients (P = .005) and HI (P < .0001), as was for PBVC in MS patients (P = .001), but not for HI (P = .521). There was a significant aging interaction effect in the annualized PLVVC (P = .001) between HI and MS patients, which was not observed for the annualized PBVC (P = .380). Development of brain atrophy manifests progressively in MS patients, and occurs with a different pattern, as compared to aging HI. PLVVC increased across age in HI as compared to MS, while PBVC decreased across ages in both HI and MS.

Cesarean delivery and artificial lactation are associated with an earlier age of disease onset in multiple sclerosis (P2.350)

Cesarean delivery and artificial lactation are associated with an earlier age of disease onset in multiple sclerosis (P2.350)

Higher latitude is significantly associated with an earlier age of disease onset in multiple sclerosis

BackgroundAge at onset (AAO) in multiple sclerosis (MS) is an important marker of disease severity and may have prognostic significance. Understanding what factors can influence AAO may shed light on...

Factors associated with onset, relapses or progression in multiple sclerosis: A systematic review

Multiple sclerosis (MS) is a chronic disease of the central nervous system with an unidentified etiology. We systematically reviewed the literature on the possible risk factors associated with MS disease onset, relapses and progression from 1960 to 2012 by accessing six databases and including relevant systematic reviews, meta-analyses, case-control or cohort studies. The focus was on identifying modifiable risk factors. Fifteen systematic reviews and 169 original articles were quality assessed and integrated into a descriptive review. Best evidence, which included one or more prospective studies, suggested that lower exposure to sunlight and/or lower serum vitamin D levels were associated with an increased risk of developing MS onset and subsequent relapses, but a similar quality of evidence was lacking for disease progression. Prospective studies indicated that cigarette smoking may increase the risk of MS as well as accelerate disease progression, but whether smoking altered the risk of a relapse was largely unknown. Infections were implicated in both risk of developing MS and relapses, but data for progression were lacking. Specifically, exposure to the Epstein-Barr virus, particularly if this manifested as infectious mononucleosis during adolescence, was associated with increased MS risk. Upper respiratory tract infections were most commonly associated with an increase in relapses. Relapse rates typically dropped during pregnancy, but there was no strong evidence to suggest that pregnancy itself altered the risk of MS or affected long-term progression. Emerging research with the greatest potential to impact public health was the suggestion that obesity during adolescence may increase the risk of MS; if confirmed, this would be of major significance.

Offspring Number Does Not Influence Reaching the Disability's Milestones in Multiple Sclerosis: A Seven-Year Follow-Up Study.

Objectives: data on pregnancy long-term effects on multiple sclerosis (MS) course are still controversial; whether experiencing more than one pregnancy exposes one to risk of the disability‘s accrual is still unknown. We investigated differences existing in terms of disability progression among women with MS (wwMS) who had one or more children after their MS onset. Methods: Monoparous and multiparous wwMS were enrolled from the Catania MS Center, Italy, in a monocenter retrospective study. A Cox proportional hazards model was used to examine the effect of the number of parities on time from MS disease onset to EDSS 4.0 and 6.0. The study protocol was approved by the local Ethical Committee. Results: during the seven years of observation, 32.1% and 23.2% of the monoparous group reached expanded disability disease status (EDSS) 4.0 and 6.0 respectively, compared to 13.3% and 3.3% of the multiparous group (p = 0.057 and p = 0.017; respectively). The Kaplan–Meier curve analysis showed no statistically-significant differences between the two groups in reaching the two milestones. The multiparous group showed a longer time to reach the EDSS 4.0 (3.5 vs. 2.6 years, log-rank 0.57, p = 0.45). The Cox regression analysis showed that the EDSS at the time of first pregnancy (Exp(B) 9.4, CI 4.5–19.7, p < 0.001) and the time from MS onset to first pregnancy (Exp(B) 0.96, CI = 0.93–0.98, p < 0.05) were significant predictors of reaching the EDSS 4.0, whereas a model including only the EDSS one year after the first pregnancy significantly predicted (Exp(B) value of 6.4, CI 2.6–15.4, p < 0.001) the reaching of EDSS 6.0. Conclusions: Our results suggest that experiencing more than one pregnancy could not convey a different clinical outcome in wwMS. Further research is needed to confirm our results.

Site-specific clinical disease onset in multiple sclerosis.

Multiple sclerosis is a chronic inflammatory disorder of the central nervous system characterized by acute episodes of neurological dysfunction thought to reflect focal areas of demyelination occurring in clinically eloquent areas. These symptomatic relapses are generally considered to be random clinical events occurring without discernible pattern. The hypothesis that relapses may follow a predetermined sequence and may provide insights into underlying pathological processes was investigated. Employing prospective clinical database data from 1482 patients who had experienced one or more consecutive relapses were analysed. Using regression analysis, site and symptom of index event were compared with those of first relapse. It is demonstrated that following disease ignition subsequent relapses may not be random events but dependent on characteristics of the index event. All anatomical sites were more likely to be affected in the first relapse if that site had been involved in the index event with a similar association observed when comparing by symptoms. These findings have importance in understanding the evolution of the disease and predicting individual disease progression and may aid with patient counselling and management.

Parity Associated with Long-Term Disease Progression in Women with Multiple Sclerosis

Background: Pregnancy in multiple sclerosis (MS) is marked by a decrease in relapse activity with a corresponding rebound in the first months postpartum. Because MS typically occurs during childbearing years, it is important to determine the long term effect of pregnancy. Design/Methods: Subjects were part of the New York State Multiple Sclerosis Consortium registry. 1,195 parous and 328 nulliparous women with clinically definite MS age 45 or older were analyzed to determine time to a disability milestone, Expanded Disability Status Scale (EDSS) 6.0. A Cox proportional hazards model was used to examine the effect of parity on time from MS disease onset to EDSS 6.0, adjusted for confounding factors. Results: The average disease duration for 1,523 women was 18.1 years. During a mean follow-up period of 5.6 years 23.1% of the parous group reached EDSS 6.0, compared to 26.5% of the nulliparous women. Cox survival curves between parous and nulliparous women were significantly different (HR=.68, CI=.53-.87, p=.002), with parous women showing a longer time to reach the disability outcome. Follow-up analyses stratified by MS type showed that parity remained a significant predictor of disease progression in relapsing remitting (RRMS) patients, whereas this effect was not observed within progressive subtypes. Conclusions: Our results demonstrate that parous women with RRMS take a longer time to reach a well-defined disability milestone (i.e. use of cane) compared to nulliparous women, suggesting that pregnancy may convey a long term benefit. Further research is needed to determine why pregnancy might be protective against long term MS disability progression.

Association analysis of nitric oxide synthases: NOS1, NOS2A and NOS3 genes, with multiple sclerosis

Background: Multiple sclerosis (MS) is a chronic inflammatory autoimmune disorder of the central nervous system.Aim: To explore the genetic basis of three nitric oxide synthase (NOS) genes: NOS1, NOS2A and NOS3, with susceptibility to MS.Subjects and methods: A total of 122 MS patients and 118 healthy controls screened for NOS1 (rs2682826, rs41279104), NOS2A (CCTTT)n/(TAAA)n and NOS3 (rs1800783, rs1800779, rs2070744, 27bpVNTR) markers, using TaqMan®SNP Genotyping Assays and fragment analysis were enrolled in this study. QRT-PCR and ELISA were used to analyse the expression of NOS3 mRNA and Nitric Oxide (NO) levels.Results: Two NOS3 markers were associated with susceptibility to MS and early disease development. The NOS3 rs1800779 G-allele (p = 0.04) and GG-genotype (p = 0.02) showed association with susceptibility to MS. Short NOS2 (CCTTT)n (p = 0.03) and short/long repeat (p = 0.04) genotypes also showed associations with MS. These associations were intensified by sub-division of patients into Kuwaiti Arabs and Persians (p < 0.05). The NOS3-27 bp-VNTR a-allele was associated with early MS disease onset ≤26 years (p = 0.04). The NOS3-27 bp-VNTR a/b-genotype resulted in 23% lower NO production and the NOS3-rs1800779 AA-genotype resulted in lower NOS3 expression. Haplotypes obtained from NOS2A and NOS3 showed increased susceptibility to MS. NOS1 showed no significant association with MS.Conclusion: This study provides evidence for the association between selected NOS2 and NOS3 markers and MS susceptibility.

PAW27 Age-dependent phenotypic variation of multiple sclerosis at disease onset

Clinical details of disease onset in multiple sclerosis (MS) are valuable, providing insight into disease outcome. Age is recognised as an important modifying factor for prognosis and may also exert...

Multiple sclerosis as a vascular disease

Multiple sclerosis (MS) has traditionally been viewed and researched as an immune-mediated disease with principal emphasis on the role of activated inflammatory cells, oligodendrocytes and astrocytes in its pathogenesis. Abnormalities of cerebral endothelial cells (CECs) is an under explored facet of MS pathogenesis and vascular abnormalities play a crucial role in formation of the MS lesions and disease progress, at least in the initial stages of disease. This review will focus on MS as a central nervous system (CNS) disease with a strong vascular constituent and examines abnormalities within CECs in MS and their role in the loss of blood–brain barrier and transendothelial migration of activated leukocytes into the CNS. One goal of this paper is to persuade and promote research on the endothelial abnormalities in pathogenesis of MS and to exploit existing knowledge on endothelial injury. A deeper understanding of endothelial pathophysiology in MS may help develop effective treatments through stabilization of endothelial function, translating into delay or arrest of MS disease onset and disability in MS patients.